Add support for backdoor_port to be returned with a rpc call.

This adds an rpc call for compute and network that will return
the eventlet_backdoor port for the service.

Change-Id: I95fdb5ca9bce9f3128300e3b5601fb2b2fc5e82f
Signed-off-by: Matthew Treinish <treinish@linux.vnet.ibm.com>

nova/common/eventlet_backdoor.py

@@ -64,7 +64,7 @@ backdoor_locals = {
 
 def initialize_if_enabled():
     if CONF.backdoor_port is None:
-        return
+        return None
 
     # NOTE(johannes): The standard sys.displayhook will print the value of
     # the last expression and set it to __builtin__._, which overwrites
@@ -76,6 +76,8 @@ def initialize_if_enabled():
             pprint.pprint(val)
     sys.displayhook = displayhook
 
-    eventlet.spawn(eventlet.backdoor.backdoor_server,
-                   eventlet.listen(('localhost', CONF.backdoor_port)),
+    sock = eventlet.listen(('localhost', CONF.backdoor_port))
+    port = sock.getsockname()[1]
+    eventlet.spawn(eventlet.backdoor.backdoor_server, sock,
                    locals=backdoor_locals)
+    return port

nova/manager.py

@@ -140,6 +140,7 @@ class Manager(base.Base):
             host = CONF.host
         self.host = host
         self.load_plugins()
+        self.backdoor_port = None
         super(Manager, self).__init__(db_driver)
 
     def load_plugins(self):

nova/service.py

@@ -111,7 +111,7 @@ class Launcher(object):
 
         """
         self._services = []
-        eventlet_backdoor.initialize_if_enabled()
+        self.backdoor_port = eventlet_backdoor.initialize_if_enabled()
 
     @staticmethod
     def run_server(server):
@@ -131,6 +131,8 @@ class Launcher(object):
         :returns: None
 
         """
+        if self.backdoor_port is not None:
+            server.backdoor_port = self.backdoor_port
         gt = eventlet.spawn(self.run_server, server)
         self._services.append(gt)
 
@@ -382,6 +384,7 @@ class Service(object):
         self.periodic_fuzzy_delay = periodic_fuzzy_delay
         self.saved_args, self.saved_kwargs = args, kwargs
         self.timers = []
+        self.backdoor_port = None
 
     def start(self):
         vcs_string = version.version_string_with_vcs()
@@ -400,6 +403,9 @@ class Service(object):
 
         self.manager.pre_start_hook()
 
+        if self.backdoor_port is not None:
+            self.manager.backdoor_port = self.backdoor_port
+
         self.conn = rpc.create_connection(new=True)
         LOG.debug(_("Creating Consumer connection for Service %s") %
                   self.topic)
@@ -578,6 +584,7 @@ class WSGIService(object):
                                   port=self.port)
         # Pull back actual port used
         self.port = self.server.port
+        self.backdoor_port = None
 
     def _get_manager(self):
         """Initialize a Manager object appropriate for this service.
@@ -612,6 +619,8 @@ class WSGIService(object):
         if self.manager:
             self.manager.init_host()
             self.manager.pre_start_hook()
+        if self.backdoor_port is not None:
+            self.manager.backdoor_port = self.backdoor_port
         self.server.start()
         if self.manager:
             self.manager.post_start_hook()